1. Technical Field
The present invention relates to a drill guide for guiding a drill to be used for forming, between plural bone tunnels, a link bone tunnel for connecting the plural bone tunnels. More specifically, the present invention relates to a drill guide which is suitably used for forming a bone tunnel having a rectangular or elliptical opening that is suitable to transplant a tendon acquired from another part in the knee joint or the like in, for example, reconstruction of a torn anterior cruciate ligament.
2. Description of the Related Art
As is well known, in reconstruction of a torn anterior cruciate ligament (ACL), it is necessary to bore, through a bone of the knee joint at a proper location, a bone tunnel that is necessary to transplant a tendon acquired from another part in the knee joint. A common method that has been employed so far for this purpose is to bore a circular bone tunnel through a bone of the knee joint at a proper location by a hollow drill, insert a bone piece of an end portion of a transplantation tendon into the circular bone tunnel, and fix the bone piece to the bone with fixing screws.
However, for a circular bone tunnel, when a bone piece of a transplantation tendon is inserted, the stability (i.e., fitting) of the inserted bone piece is low. The present inventors have proposed forming a bone tunnel having a rectangular or elliptical opening that is high in conformity to the surface of a bone piece of a transplantation tendon by forming plural (two) circular bone tunnels, connecting them by forming a link bone tunnel between them using a drill, and then expanding a connected bone tunnel with a dilator into a rectangular or elliptical shape or cutting with a chisel.
Incidentally, as a drill guide for guiding a drill for cutting between plural bone tunnels, known is a guide member for a dental drill whose end face has a cutting blade (JP-A-2006-102002). This guide member is used in forming, in the jaw bone, using the above dental drill, a tunnel corresponding to a regenerated tooth root of double root which has two branch roots. The guide member includes an elliptical plate-like portion for covering two adjoining holes, leg pieces disposed at the two respective ends of the plate-like portion and to be inserted into the two respective holes, and a drill insertion hole provided in the center of the plate-like portion
Also known is a surgical drill guide assembly which includes alignment drill pipes for receiving and guiding surgical drill bits, a bushing having an expandable front end portion which supports the alignment drill pipes, and a drill guide assembly handle which is connected to the bushing (JP-T-2003-531666). The front end portion of the bushing is expanded in a bone plate, whereby the bushing is locked being spaced from bone plate fastener holes and the alignment drill pipes are aligned with corresponding fastener holes.